Recently, display devices using, for example, liquid crystal display elements or organic electroluminescent display elements must exhibit a reduced frame area around the display area in which images are displayed.
In the frame area, peripheral circuits such as a driver for driving pixels provided in the display area are formed. The peripheral circuits comprise, for example, CMOS circuits including p- and n-type transistors. If the size of a semiconductor element such as a CMOS circuit is reduced, it is possible to reduce the frame area.
A small-sized semiconductor element may bring about favorable effects even when it is used for the circuit of other types of devices instead of the peripheral circuit of display devices. For example, the small-sized semiconductor element will reduce the size of the entire device.